The towline exerts a force of p = 4 kn at the end of the 20-m-long crane boom. if u = 30, determine the placement x of the hook at a so that this force creates a maximum moment about point o . what is this moment?

Is there any opitions? if you have the periodic table, the noble gases are 8a family, the halogen are the 7a family, and the nonmetal are  carbon, nitrogen, phosphorus, oxygen, sulfur, selenium, fluorine, chlorine, bromine, iodine and astatine.